Trim visible fat from steak. Place steak in a large resealable bag with 1/4 cup soy sauce. Place in the refrigerator and let marinate for about 1 hour.
Meanwhile, dice mango and red pepper and shred carrots. Cook edamame if frozen.
Whisk together all sauce ingredients.
Remove steak from the refrigerator. Place on a plate and season liberally with freshly cracked black pepper and garlic powder.
Preheat a large skillet over high heat. Once hot, add sesame oil. Sear steak for about 1-2 minutes per side. Remove from heat and set on a plate to rest.
While steak is resting, bring water to a boil in a large saucepan and cook noodles according to package directions. Drain and toss noodles with the sauce.
To assemble bowls, split noodles between 4 bowls. Divide mango, pepper, edamame and carrots between bowls. Top each bowl with sliced steak and sprinkle with basil. Serve hot or toss everything and refrigerate to serve cold.